Schmitt



A. SCHMITT March 24, 1964 METHOD OF APPLYING A COATING TO THE SURFACES OF A HEEL Filed Sept. 6, 1961 A/bmqs United States Patent METHOD OF APPLYING A COATING TO THE SURFACES OF A HEEL Alois Schmitt, 126 Aschafienburger Strasse, Goldbach uber Aschaffenburg, Germany Filed Sept. 6, 1961, Ser. No. 136,233

Claims priority, application Germany Sept. 9, 1960 9 Claims. (Cl. 12-147) The present invention relates to a method of applying a plastic coating to the surfaces of a heel so that the plastic coating is tightly drawn thereon and a wrinkle-free finish is obtained.

Shoe heels which are made from material other than leather are usually covered with a material which is first cut out in a shape to conform to the rear part of the heel and then secured to the heel with an adhesive. The disadvantage of applying a covering to a heel in this manner is that the covering does not closely conform to the shape of the heel because of its thickness. In addition, special steps had to be taken to smooth the top edge of the covering at the top of the heel so that the heel could be fitted closely to the heel portion of the shoe. Also, the edges of the covering at the front of the heel were made flush with the front surface. However, this resulted in the edge of the covering being susceptible to chipping and subsequent peeling of the coating. In view of the exact fitting of this coating as described above, this type of heel covering was expensive and the heels, of necessity, had to be individually processed.

Subsequently, a plastic sheet covering was applied to heels which Were not made from leather. However, this type of covering invariably resulted in a wrinkled surface so that such heels were commercially unacceptable.

It is, therefore the principal object of this invention to provide a novel and improved-process of applying a plastic coating to a heel which is made of a material other than plastic. I

In a process of the present invention the heel is positioned on a mounting of a vacuum forming machine. This mounting is located upon a platform that can be raised and lowered. The rear side of the heel is directed upwardly towards a plastic sheet which is stretched by a frame over an opening in the machine. The surface of the plastic sheet directed towards the heel is coated with an adhesive and the sheet is then heated to about 100 C. by the use of an infrared heater.

Other objects and advantages of this invention will be apparent upon reference to the accompanying description when taken in conjunction with the following drawings, wherein FIGURE 1 is a vertical sectional view of the apparatus of this invention for applying a plastic coating to a heel and showing the heels mounted therein;

FIGURES 2, 3 and 4 are side, front and top views, respectively, of a heel formed by the process of this invention.

Proceeding next to the drawings wherein like reference symbols indicate the same parts throughout the various views, FIGURE 1 illustrates the apparatus used for coating the heels with plastic. This apparatus is adapted to form an enclosure which can be hermetically sealed to provide a vacuum chamber after bringing a platform 2 into vacuum-tight engagement with a rubber gasket 16. The apparatus for raising and lowering the platform 2 is not shown.

The platform 2 is moved up against the gasket ring 16, whereby the rear portion of the heel 6 is pressed into the plastic film while the plastic film is pushed out of the plane of its supporting frame in such a manner that the film will engage the greater portion of the back of the ice heel smoothly and without folds. The air is then immediately removed from the vacuum space that is formed by the film 15, the gasket rings 12, 16, the edge of the opening 11 and the platform 2, preferably through a hollow rod 2a passing through the platform 2. By such a procedure the film will also be brought around to the front of the heel and around the edges of the base of the heel to obtain a smooth, wrinkle-free coating.

The platform 2 carries two vertically upstanding walls 3 through which are passed a plurality of shafts 4 fixedly or rotatably positioned to carry mountings 5 for the heels 6. The mountings are for the purpose of supporting heels 6 therein in a manner shown in FIGURE 1.

The mounting 7 comprises a pair of vertical stop members 8 and 9 with the member 9 being adjustable and provided with a movable portion 10 so that heels 6 of different heights can be tightly secured in the mounting.

In the top surface of the enclosure 1 there is provided an opening 11 which is surrounded by a rubber gasket 12. Another gasket 14 and a frame 13 are positioned above a plastic sheet 15 which is supported between the gaskets 12 and 14. Means are provided for clamping the frame 13 to the enclosure to tightly secure the plastic sheet 15 above the opening 11.

On the lower side of the top of the enclosure 1 there is another rubber gasket 16 which surrounds the opening 11. The gasket 16 cooperates with the platform 2 so as to form a vacuum-tight seal therewith.

While only three mountings are shown in the present apparatus it is to be understood that more or less mountings can readily be positioned therein.

The aforementioned pump for exhausting the enclosure is connected to a hollow rod 2a upon which the platform 2 is mounted. As soon as the platform 2 has been brought tightly against the gasket ring 16, the air from the space between the plastic film 15 and the platform 2 is evacuated through the hollow rod 2a by an air pump.

In order to apply a plastic coating to a heel according to the present invention, the following process is carried out.

The inner side of the plastic sheet 15, i.e., the side directed to the top surface of the heel when it is positioned as shown in FIGURE 1, is coated with a primer. An adhesive is then applied to the primed surface. The heels 6 are also coated with an adhesive and are so positioned in the mountings 5 that the rear or curved sides are directed upwardly towards the plastic sheet 15. The bottom or tread surface of the heel 6 abuts against the vertical stop member 8 and the adjustable portion 10 abuts against the top surface of the heel.

The stretched plastic sheet thus forms a hermetic seal over the opening 11 of the apparatus. The plastic sheet is then heated to about C. by means of an infrared heating device which is movably mounted above the plastic sheet (not shown). The platform 2 is then moved upwardly towards the plastic sheet so as to engage the rubber gasket 16. This produces a vacuum-tight enclosure between the platform 2 and the plastic sheet 15.

Since the heated plastic sheet is extremely flexible, the heels are pressed into the plastic sheet to move the sheet upwardly out of the plane of the frame and the sheet will wrap around a large portion of the upper surface of the heel 6. When a vacuum is applied after the platform 2 has engaged gasket 16 to the underside of the plastic sheet, the sheet will become tightly drawn around the edges of the rear surfaces of each of the heels 6 including the beds thereof. In addition, portions of the sheet will surround the front side of the heel and the top side of the heel.

Cooling air is then directed on the outer surface of the heel to bring about a quicker cooling of the plastic sheet and to secure a quicker adherence to the heel.

The surplus portions of the plastic sheet are then cut off at the front and top of the heel by any suitable means including an electrically heated and suitably curved knife, or scissors. This forms flaps or edges 1% and 19 which can then be tightly pressed against their respective surfaces by means of a rapidly rotating shaft which has a rotary speed of approximately 5000 revolutions per minute.

Since the plastic is quite thin, the edges 19 on the top of the heel will present very little, if any, interference with the sole of the shoe to which the heel is fastened.

Various types of plastic sheets may be used to cover the heel. When the heel 6 is to be covered with a plastic sheet which has a grain on its side, the mountings must be pivoted about the shafts 4 and retained in a suitable position so that the grain is substantially parallel with respect to the treading surface of the heel. Such a grain is indicated at 17 in FIGURE 2.

The plastic sheet may comprise various colors, designs and ornamentations on the side thereof to which the adhesive is supplied. Further, the plastic sheet may be provided with simulated grain. Such a grain may simulate leather. In this case, the outer surface of the plastic sheet may be provided with parallel grooves by means of which the parallel grain markings are separated from each other on the surface of the heel.

The transparent plastic sheet can also be lacquered or sprayed with metal pigments or metallic particles can be deposited on the plastic sheet by evaporation in a high vacuum process. The coloring materials which can be applied to the plastic sheet may comprise phosphorescent, fluorescent materials or reflecting materials added thereto.

The transparent plastic foil may have an adhesive coating on only one side with a design or coloring printed on the uncoated side. The uncoated side can then be subsequently covered with another transparent plastic sheet which has an adhesive coating on one side thereof.

The plastic sheet may have an adhesive coating on both sides thereof with a design being printed on one of the sides which side is then covered with a transparent plastic sheet which has no adhesive coating thereon.

Thus it can be seen that the present invention discloses a process for covering a heel with a plastic sheet which is deep-drawn on the heel in such a manner that a wrinklefree plastic coating is obtained and the plastic is secured to the heel by an adhesive.

The plastic sheet which is to be applied to the heel may also be formed with parallel grooves or ridges on the side thereof which is to be applied to the heel. These ridges are somewhat offset from each other so as to form a step effect as illustrated in FIGURES 2 and 3. In addition, the plastic sheet may be provided on its other sides with grooves which are also parallel to the grooves or ridges on the inner side. The use of this grooved plastic material provides increased strength for the coating and also enables the plastic to be constructed to simulate a leather covering.

When this grooved plastic is used, it is generally desired that the grooves be parallel to the treading surface of the heel. Accordingly, the heel mounting 5 is pivoted to the position wherein these grooves will be parallel to the treading surface and then locked in position. By the use of these pivotable heel mountings a variety of diiferent effects may be achieved, using various plastic sheets as coverings.

It will be understood that this invention is susceptible to modification in order to adapt it to different usages and conditions and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

What is claimed as this invention is:

1. A method of covering a shoe heel made of a material other than leather with plastic sheet material, and comprising the steps of positioning the heel horizontally upon an upwardly movable platform with the rear surface of the heel being directed upwardly, stretching an adhesive coated plastic sheet above the heel with the adhesive coating directed towards the heel, heating the plastic sheet material to a temperature of about C., moving platform and the heel upwardly to bring the heel against the plastic sheet so that the sheet engages a portion of the rear surface of the heel, exhausting the atmosphere between the sheet and the platform to produce a subatmospheric pressure under the sheet so that the plastic sheet will be closely drawn around the entire rear surface of the heel and the edges of the top and front faces of the heel to form a wrinkle-free covering thereon, and cutting away the portions of the sheet beyond the top and front faces of the heel.

2. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet is provided with parallel lines printed on the side directed away from the heel.

3. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet is transparent and is provided with ornamentation on the side having the adhesive coating.

4. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet is transparent and is provided with a metallic coating.

5. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet is transparent and is provided with a coating of luminescent material.

6. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet has a design printed on the side directed away from the heel, and the further step of covering this ornamented side with a transparent plastic sheet having an adhesive coating thereon.

7. A method of covering a shoe heel as claimed in claim 1 wherein said plastic sheet has adhesive coatings on both sides with a design being printed on one side, and the further step of covering the heel with a transparent plastic sheet.

8. A method of covering a shoe heel as claimed in claim 1 and comprising the tfllIIhCI' step of rotating the heel to activate the adhesive thereon so that the edges of the plastic sheet can be glued onto the front and top of the heel without the necessity for reheating the adhesive.

9. A method of covering a shoe heel made of a material other than leather with plastic sheet material, and comprising the steps of positioning the heel horizontally upon an upwardly movable platform with the rear surface of the heel being directed upwardly, stretching an adhesive coated plastic sheet above the heel with the adhesive coating directed towards the heel, heating the plastic .sheet material to a temperature of about 100 (3., moving the platform and the heel upwardly to bring the heel against the plastic sheet so that the sheet engages a portion of the rear surface of the heel, exhausting the atmosphere between the sheet and the platform to produce a sub-atmospheric pressure under the sheet so that the plastic sheet will he closely drawn around the entire rear surface of the heel and the edges of the top arid front faces of the heel to form a wrinkle-free covering thereon, cutting away the portions of the sheet beyond the top and front faces of the heel, and directing a stream of cooling air onto the outer surface of the heel after the plastic sheet has been glued thereto.

References Cited in the file of this patent UNITED STATES PATENTS 2,015,656 Bazzoni Oct. 1, 1935 2,032,449 Tetlow Mar. 3, 1936 2,123,839 Beyer et al. July 12, 1938 2,161,452 Burger June 6, 1939 2,236,552 Ushakolf Apr. 1, 1941 2,255,941 Rule et al. Sept. 16, 1941 2,569,070 ODonnell Sept. 25, 1951 2,781,077 Dovidio Feb. 12, 1957 2,972,760 Lipp Feb. 28, 1961 

1. A METHOD OF COVERING A SHOE HEEL MADE OF A MATERIAL OTHER THAN LEATHER WITH PLASTIC SHEET MATERIAL, AND COMPRISING THE STEPS OF POSITIONING THE HEEL HORIZONTALLY UPON AN UPWARDLY MOVABLE PLATFORM WITH THE REAR SURFACE OF THE HEEL BEING DIRECTED UPWARDLY, STRETCHING AN ADHESIVE COATED PLASTIC SHEET ABOVE THE HEEL WITH THE ADHESIVE COATING DIRECTED TOWARDS THE HEEL, HEATING THE PLASTIC SHEET MATERIAL TO A TEMPERATURE OF ABOUT 100*C., MOVING PLATFORM AND THE HEEL UPWARDLY TO BRING THE HEEL AGAINST THE PLASTIC SHEET SO THAT THE SHEET ENGAGES A PORTION OF THE REAR SURFACE OF THE HEEL, EXHAUSTING THE ATMOSPHERE BETWEEN THE SHEET AND THE PLATFORM TO PRODUCE A SUBATMOSPHERIC PRESSURE UNDER THE SHEET SO THAT THE PLASTIC SHEET WILL BE CLOSELY DRAWN AROUND THE ENTIRE REAR SURFACE OF THE HEEL AND THE EDGES OF THE TOP AND FRONT FACES OF THE HEEL TO FROM A WRINKLE-FREE COVERING THEREON, AND CUTTING AWAY THE PORTIONS OF THE SHEET BEYOND THE TOP AND FRONT FACES OF THE HEEL. 